Exact Solution of Effective Mass Schrödinger Equation for the Hulthen Potential

A general form of the effective mass Schrödinger equation is solved exactly for Hulthen potential. Nikiforov-Uvarov method is used to obtain energy eigenvalues and the corresponding wave functions. A free parameter is used in the transformation of the wave function.     

Characterisation of gold gilt silver wires from five embroidered silk Qaaba curtains dated between the 16th and 19th centuries

The wires from five Qaaba curtains, dated between the 16th and 19th centuries, presently exhibited at the Topkapı Palace Museum in Istanbul, and embroidered with gold gilded silver and silver wires, were characterized physically and chemically. The curtains are part of the Kiswa, the cover of the Qaaba, the holy place of pilgrimage in Mecca for Muslims. Scanning electron microscope (SEM) (including field emission sem) studies were carried out using energy dispersive spectrometry (EDS) as well as atomic absorption spectroscopy (AAS), and inductively coupled plasma (ICP) for chemical analysis. The chemical and physical composition of the wires and their coatings, and the analysis of corrosion products were made, and the present state of the wires were evaluated and compared. PACS 81.05.Bx; 81.70.Jb; 82.80.Ej; 68.37.Hk; 68.37.Vj     

Klein–Gordon and Dirac Equations with Thermodynamic Quantities

We study the thermodynamic quantities such as the Helmholtz free energy, the mean energy and the specific heat for both the Klein–Gordon, and Dirac equations. Our analyze includes two main subsections: (1) statistical functions for the Klein–Gordon equation with a linear potential having Lorentz vector, and Lorentz scalar parts (2) thermodynamic functions for the Dirac equation with a Lorentz scalar, inverse-linear potential by assuming that the scalar potential field is strong (A ? 1). We restrict ourselves to the case where only the positive part of the spectrum gives a contribution to the sum in partition function. We give the analytical results for high temperatures.     

Solvent-controlled selective transformation of 2-bromomethyl-2-methylaziridines to functionalized aziridines and azetidines

The reactivity of 2-bromomethyl-2-methylaziridines toward oxygen, sulfur, and carbon nucleophiles in different solvent systems was investigated. Remarkably, the choice of the solvent has a profound influence on the reaction outcome, enabling the selective formation of either functionalized aziridines in dimethylformamide (through direct bromide displacement) or azetidines in acetonitrile (through rearrangement via a bicyclic aziridinium intermediate). In addition, the experimentally observed solvent-dependent behavior of 2-bromomethyl-2-methylaziridines was further supported by means of DFT calculations.     

Analog image recognition arrays design by using co-fabricated MOSFET and MESFETs on a 0.25?μm SOS process

This paper presents an analog image recognition system with a novel MESFET device fabricated on a fully depleted (FD) CMOS process. An analog image recognition system with a power consumption of 2.4?mW/cell and a settling time of 6.5???s was designed, fabricated and characterized. A CNN is employed to realize a core cell of the proposed image recognition system. While a CNN benefits from its regular structure, it faces challenges due to its power consumption, speed, and size in their CMOS implementations. SOS MESFETs can deal with the challenges associated with CMOS-based CNNs. Advantages of SOS MESFETs associated with nonlinear signal processing include lower power consumption and higher operating speeds compared to similar geometry MOSFETs carrying the same current. SOS MESFET-based analog image recognition systems were fabricated and the transient response is characterized in both simulation using a TOM3 SPICE model extracted from SOS MESFETs and in experiment using image testing lab equipment. Settling times of 3.5 and 6.5???s for one-by-four and one-by-eight arrays, respectively, were achieved with line recognition template. The corresponding power consumption for the two arrays was 9.6 and 19.2?mW, respectively.     

Stability analysis of N-model systems under a static priority rule

We consider the stability of N-model systems that consist of two customer classes and two server pools. Servers in one of the pools can serve both classes, but those in the other pool can serve only one of the classes. The standard fluid models in general are not sufficient to establish the stability region of these systems under static priority policies. Therefore, we use a novel and a general approach to augment the fluid model equations based on induced Markov chains. Using this new approach, we establish the stability region of these systems under a static priority rule with thresholds when the service and interarrival times have phase-type distributions. We show that, in certain cases, the stability region depends on the distributions of the service and interarrival times (beyond their mean), on the number of servers in the system, and on the threshold value. We also show that it is possible to expand the stability region in these systems by increasing the variability of the service times (without changing their mean) while keeping the other parameters fixed. The extension of our results to parallel server systems and general service time distributions is also discussed.